We're in the middle of the current school year, but it's not too early to start thinking about the next. Especially for parents considering applying to charters schools for the 2015-2016 school year.

Since the first charter school opened in New York City in 1999, the public, independently-run schools have grown at an average of 11 schools a year, with nearly 200 currently operating across all five boroughs and more on their way. Still, the current offerings aren't enough to meet the demand -- last year, 70,700 students applied for 21,000 seats.

We talked with James Merriman, CEO of the New York City Charter School Center, which supports new and existing charter schools, to find out more about the growth of charter schools in NYC and why they are becoming a sought-after option.

What's the biggest change for NYC's charter schools in the past 15 years?

I think the biggest change is the number of schools that we now have -- this year we have 197 schools, educating some 83,000 students -- the fact that there are more choices in more places, with more parents looking at charter schools as options.

Why has it experienced such growth?

Parents are affirmatively choosing the schools, the same they do within the district schools, schools that they feel fits for their children, they like the programs, the environment, the sense of rigor that many of the charter schools have, and so they're affirmatively choosing in. And unfortunately, sometimes the truth is, as the mayor himself said is, the district schools are simply failing their children and are broken in many respects. And so you have parents who sometimes are not so much running towards charter schools, but running away from failed district schools.

Why can charters potentially have better outcomes?

To give a simple description is impossible because the whole idea of charters is to have independent schools. That said, I think parents appreciate the kind of attention they often get, the sense that they are valued partners in their child's education, and a longer school day and a longer school year. Education research shows that with low-socioeconomic-status children, most backslide during the summer. The less summer there is, many parents understand, the better.

What would you say to parents debating applying?

What we worked very hard over the years is to make it as easy as possible to apply. One of the things we've created, and that most charter schools participate in, is an online common charter school application. In the past, you might have had to go out to each individual charter schools and get the application, but you can now go online at www.nyccharterschools.org, sort through all charter schools through a variety of criteria, such as all charters that provide kindergarten in [Community School District] 17, and apply to every school within that CSD. The truth is, schools are oversubscribed, and there are long waiting lists at many of them, but I would say to parents, nothing ventured, nothing gained.

What are the biggest challenges for growth?

No. 1 is we want to make sure we have sufficient funding for schools to both put a roof over their heads and provide a program that students deserve, in terms of richness and staffing and high-quality staff there. No. 2 is the number of charters that are available [to be created in New York] is getting smaller. Our view is that it isn't time to lift a cap, it's time to eliminate it.

The New York City Charter School Center will host a charter fair at Dream Charter School, 232 E. 103rd St., March 14 from 10 a.m.-2 p.m. Visit nyccharterschools.org for more.

WHAT YOU NEED TO KNOW ABOUT NYC CHARTER SCHOOLS

Who can apply?

The short answer is: anyone. Charter schools are open to all children, beginning with kindergarten, regardless of their grades or needs.

How do you apply?

Each school sets its own admissions process, so you should check with each school individually for guidance. Students can apply to more than one school. Some, but not all schools use a common application.

When's the deadline?

Each school has different deadlines for applications, though most are due by April 1 if not earlier. If you miss the deadline you can still apply, but your child will be placed at the bottom of the waitlist.

Who's accepted?

Students are accepted on a first-come, first-served basis. When more applications are received than seats available, the school will hold a random admissions lottery. By law, charter schools must give preference to returning students, siblings of currently enrolled students and students who live in the community school district where the charter school is located. Students not selected are put on a waitlist.